Recent developments in mass spectrometry have opened exciting new avenues in geochemistry. Plasma source mass spectrometry has brought together groups who previously retained their identity through different forms of mass spectrometry. Those with thermal ionization mass spectrometers analysed radiogenic isotopes, commonly of Sr, Nd and Pb, and the stable isotopes of H, C, O and S were analysed on gas source machines. Very few had experience with plasma sources, and this mass spectrometry now allows high precision measurements of the stable isotopes from a range of elements including a number of metals. It involves scientists used to analysing heavier radiogenic...